This change introduced Python object statics, which has a negative impact on multiple interpreter support etc.

This reverts commit b68f2585.

Hard-disable the MergeVTables() step during the extension type setup when using the Limited API. There might be a way to make it work, but it currently won't.

Also see https://github.com/cython/cython/pull/4107

Allow searching for include/import files without passing a source pos tuple and clean up the call chains a little.

For reasons I don't full understand, including "windows.h" seems to break everything. There's an alternative sleep function in stdlib.h so I've used that instead since it makes the point just as well.

Disable __Pyx_PyType_Ready() usage in PyPy & friends where it fails to compile currently. They should generally be happy with their own implementation.
See https://github.com/cython/cython/pull/4107

Allow inheriting from cimported multiply inherited class.

Fix Python install script on appveyor: The URL path uses three digit Python versions, not just major.minor.

According to the docs, "/Od" is the default in MSVC, so in order to get it, it should be enough to clear CFLAGS.
Setting it generates warnings in Py3.9 on appveyor ("source file '"/Od"' ignored"), suggesting that the option is not recognised as such.
https://docs.microsoft.com/en-us/cpp/build/reference/od-disable-debug?view=msvc-160

Remove "PYTHONHOME" setting from embed-test since it seems to break the I/O encoding setup in (at least) Py3.8+ venvs.

Signed-off-by: Andrew V. Jones <andrew.jones@vector.com>

Closes https://github.com/cython/cython/pull/4101
See https://github.com/cython/cython/issues/4100

* Handle constant folding for LanguageLevel 2 on Python 3. Ensure that when StrNode is a BytesLiteral, that we don't coerce it to unicode.
* Add test for string multiplication bug. Needed to change the TreePath slightly to allow bytes-to-str comparison.

Fixes https://github.com/cython/cython/issues/3951

Remove incorrect dict unpacking optimisation that leaked external dict changes into the result (GH-4091)

Closes https://github.com/cython/cython/issues/3227

* Disable GC-sensitive NumPy tests on PyPy
* Removed @testcase decorator pattern that was causing tests to be run twice

Creating global CDEFS for holding compiler definitions. Then pass it to the distutils.

Also add .vscode folder to .gitignore

Fixes https://github.com/cython/cython/issues/4096

Remove incorrect dict unpacking optimisation that leaked external dict changes into the result (GH-4091)

Closes https://github.com/cython/cython/issues/3227